1. Field of the Invention
The present invention relates to a gas accumulator for storing pressurized gas, which gas accumulator has a sealed vessel. The sealed vessel is provided with at least one valve-actuated feedline and outlet line for the pressurized gas and with a particulate packing of carbon nanostructures.
2. Discussion of the Prior Art
In particular, the storage of hydrogen in conventional pressurized vessels poses great difficulties if, with respect to the vessel volume, a packing density as high as possible is to be achieved. It is generally known that gas accumulators, in which hydride-forming metal alloys in finely divided form are packed have a particularly high storage capacity. However, these gas accumulators have considerable disadvantages, in particular because of their high overall weight.
Recently, proposals have become known to use, for storing gases, in particular hydrogen, what are termed carbon nanostructures which have chemisorbing properties. One such proposal can be taken from WO 97/26082, the disclosure of which to this extent is incorporated by reference into the description of the present invention. It is mentioned there that, depending on the temperature and pressure, up to 24 liters of hydrogen can be stored per gram of the carbon nanostructure material used. With regard to the technical form of the gas accumulator, it is merely stated that the vessel is provided with a hydrogen storage bed. No information is given on the packing density of the nanostructure material.
In many applications in which stored hydrogen is to be used, it is of importance to be able to store as large a gas quantity as possible, with the smallest possible storage volume and storage weight of the gas accumulator (highest possible specific storage capacity). This requirement applies especially to mobile applications, that is to say for instance in the case of hydrogen tanks for vehicles which are operated by fuel cells. Therefore, there is a requirement for increasing further the previously attainable storage capacity of gas accumulators for pressurized gases, in particular hydrogen.